diff --git a/shell/shellIntegration.xsh b/shell/shellIntegration.xsh
index f9d6096..c2692be 100644
--- a/shell/shellIntegration.xsh
+++ b/shell/shellIntegration.xsh
@@ -25,8 +25,8 @@ __is_original_prompt = $PROMPT
 $PROMPT_FIELDS['__is_prompt_start'] = __is_prompt_start
 $PROMPT_FIELDS['__is_prompt_end'] = __is_prompt_end
 $PROMPT_FIELDS['__is_update_cwd'] = __is_update_cwd
-if 'ISTERM_TESTING' in ${...}:
+if 'ISTERM_TESTING' in @.env:
     $PROMPT = "> "
     XONSH_SUPPRESS_WELCOME = True
 
-$PROMPT = "{__is_prompt_start}{__is_update_cwd}" + $PROMPT + "{__is_prompt_end}"
\ No newline at end of file
+$PROMPT = "{__is_prompt_start}{__is_update_cwd}" + $PROMPT + "{__is_prompt_end}"